It has been known for some time that computer viruses and worms represent a significant threat to computer systems. A computer virus or worm can generally be identified as a program or set of computer instructions that is loaded onto and executed by a user's computer without the user's knowledge. A worm differs from a computer virus in that a computer virus typically attaches itself to another computer program or data file, i.e. an infected or target file, and is spread by a user's interaction with the target file, albeit unknowingly. In contrast, a worm self propagates without any user intervention. Computer viruses and worms often undesirably reduce otherwise available system resources such as memory and disrupt data stored on infected computer systems often resulting in system failure.
Recently, a new type of worm has seen increased commonality. This type of worm spreads, or replicates itself, from an infected system by automatically sending a copy of itself via e-mail to addresses identified in an address book. Examples of these types of worms include the widely disseminated “MELISSA” and “ILOVEYOU” worms. Of course, e-mail refers to the transmission of messages over communications networks, such as the global interconnection of computers and computer networks commonly referred to as the Internet. An address file, address book, or data base, acts as an electronic phone book which stores names, personal information and e-mail addresses of other users or computer systems for intended email recipients or frequently contacted e-mail addresses.
Hence, there is a need for a method and system for preventing computer worms from accessing the address book of a recipients and disseminating itself using the information or e-mail addresses contained therein.